The Sennheiser HD 660 S looks sturdy and tough at first glance, but you’ll be surprised that it actually weighs lighter than it looks. The Sennheiser HD 660 S is made mostly of plastic but don’t take this as a sign of being low quality. The plastic materials of the Sennheiser HD 660 S actually deserve a hand for the great reviews of this model because it makes the item resistant to extreme amounts of pressure and weight. Of course, the drivers and the grills on the drivers are made of stainless steel.
The design and aesthetics of the Sennheiser HD 660 S is pretty much the same with its predecessors, bearing a sleek and sophisticated design. As a successor of the HD600 and HD650, it’s not surprising that the Sennheiser HD 660 S bore the legacy trademark design.
The Sennheiser HD 660 S has a large pad and the position of the driver is located at the center. The driver performs its abilities while it is covered with large, metallic grills. Even though the drivers have to deal with multiple layers of protection, none of them actually seals the driver, upholding the open headphone design of the Sennheiser HD 660 S.
Fit and Comfort. If fresh out of the box, the Sennheiser HD 660 S may be a bit tight on the head. Several YouTube videos that feature unboxing of this item share the same first impression when worn for the first time. To be more specific, the design of the ear coupling of the Sennheiser HD 660 S is over-ear circum aural. Don’t think that the fit is not relaxing, though, as it only means that the Sennheiser HD 660 has a secure fit, making it more snug and secure than a helmet of a firefighter.
As per experience, the tight fit eventually eases up over time and becomes more comfortable. The width of the ear pad is also large enough for most ears and the material is also soft and comfy to touch. The Sennheiser HD 660 S may not be the gateway to the most comfortable listening experience on the market, but it performed well during our comfortability test, so it gets a thumbs up from us.